How much sleep did you get last night? According to "Healthy Sleep", a publication by the U.S. National Institutes of Health (NIH), in the early 1900's people used to average 9 hours of sleep a night. Today, the average adult sleeps less than 7 hours, and more than a third of adults experience significant daytime sleepiness that affects their work and social functioning. Most of us need an average of 7-8 hours sleep, and some might need more (like me!).
In these days of packed schedules, internet, and late-night television, it can require immense discipline to get to bed on time. I battle with it constantly - I run my business from home, and with 24 hour email and web access there's always one more thing I can do before I go to bed.
When I first started practicing medicine, a colleague introduced me to the work of sleep expert William Dement, founder of the Sleep Research Centre at Stanford. In a publication for physicians, Sleep Made Super Simple, Dement notes that: "Lacking its rightful place and emphasis in life and health, the dimension of sleepiness and alertness remains poorly understood and widely ignored...as a result, almost no one makes an effort to manage their schedules and commitments in a way that takes into account the crucial need for healthy and adequate sleep". Later, he comments that "many people, in fact, live their days in a kind of ‘twilight zone' of impaired alertness which they rarely recognize, and as a consequence, they fail or only partially succeed in work, study, and human relationships."
Do you know how big your sleep debt is? If you think that your body has long forgotten that all-nighter you pulled last week, you're wrong. According to the NIH report, our body produces a compound called adenosine that accumulates in our blood when we're awake, and eventually triggers drowsiness. When we sleep, our body breaks the adenosine down. If you don't get enough sleep, your adenosine levels remain high, and you'll continue to feel drowsy (and be under-productive, and likely grumpy) the following day. If you fall asleep the instant your head hits the pillow, or any time you slow down during the day, you probably have a significant sleep debt.
If you're trying to improve your health, before you sign up for that expensive program or empty your wallet buying supplements, first take a good look at your sleep habits. If you'd like to lose weight, make sure that you're getting at least 7 hours every night - any less, and your body produces less leptin hormones than it normally should. As a result, your appetite increases, and you're significantly more likely to be obese. The same goes for women who are having trouble getting pregnant: good quality sleep promotes healthy levels of sex hormones, and women who are sleep-deprived are less likely to conceive, and more likely to miscarry.
When we sleep, our bodies produce other hormones called cytokines, which help our immune system fight infections. Studies have shown that if you get the flu vaccine while sleep-deprived, you'll produce half as many antibodies (and therefore have only half the benefit), compared to people who get vaccinated after a good night's sleep.
Our body experiences inadequate sleep as stress, which increases levels of health-damaging stress hormones. Regularly scrimping on sleep may also put you at higher risk for developing mood disorders like depression, and diseases such as heart disease and diabetes. Sleep might well be our long-sought fountain of youth - if you get enough, your body has more time to regenerate your cells, and even repairs UV skin damage.
To improve your work performance, and possibly even increase your income, get to bed on time. Lack of sleep significantly slows your thinking processes, and makes it harder to focus on a task, and pay attention. According to the NIH report, if you don't get enough sleep you'll be more likely to make poor decisions, and you'll take more risks.
Get to bed earlier, and try to stay there for eight hours . Avoid caffeine, alcohol, nicotine, large meals and strenuous exercise for several hours before bedtime. Take naps to improve daytime functioning and reduce your sleep debt, but don't nap for more than an hour, or after 3 pm (that may make it harder to fall asleep at night). Make your bedroom a place dedicated to sleep and relaxation - remove the TV, and anything remotely work-related. I'll do it, too. How about committing, right now, to getting eight hours of sleep, every night, for the next month? Prepare to be shocked by how well you'll perform, look, and feel.